Adjustable slot suction box cover

ABSTRACT

An adjustable slot cover adapted to be mounted on a suction box or pipe having openings therein in communication with a source of suction. The cover includes a base which is rigidly mounted to the suction pipe. The base includes alternate lands and slots with the slots in communication with the openings in the suction pipe. A plurality of wear strips are slidably mounted on receiving land portions of the cover with dovetail or T-shaped interengagements retaining the wear strips in position. Axial positioning of the interengaging surfaces along with the lateral width of the strips determines the portion of each wear strip which covers a portion of an adjacent slot. The dovetail or Tshaped opening in the wear strips can be located off center so that strips can be turned end for end to change the width of slot. The wear strips are interchangeable so that adjustability of slot widths is thereby achieved.

[ ADJUSTABLE SLOT SUCTION BOX COVER [75] Inventor: David F. McConaughy,Delmar,

[73] Assignee: Albany International Corp., Albany,

22 Filed: Aug. 25, 1972 21 App1.No.:283,648

[ 1 Sept. 17, 1974 3,585,105 6/1971 Stuebe 162/211 Primary ExaminerS.Leon Bashore Assistant Examiner-Richard V. Fisher Attorney, Agent, orFirmKane, Dalsimer, Kane, Sullivan and Kurucz [5 7 ABSTRACT Anadjustable slot cover adapted to be mounted on a suction box or pipehaving openings therein in communication with a source of suction. Thecover includes a base which is rigidly mounted to the suction pipe. Thebase includes alternate lands and slots with the slots in communicationwith the openings in the suction pipe. A plurality of wear strips areslidably mounted on receiving land portions of the cover with dovetailor T-shaped interengagements retaining the wear strips in position.Axial positioning of the interengaging surfaces along with the lateralwidth of the strips determines the portion of each wear strip whichcovers a portion of an adjacent slot. The dovetail or T-shaped openingin the wear strips can be located off center so that strips can beturned end for end to change the width of slot. The wear strips areinterchangeable so that adjustability of slot widths is therebyachieved.

8 Claims, 8 Drawing Figures [52] U.S. C1 162/274, 162/279, 162/366,162/374 [51] Int. Cl D2lf 1/32, D21f 1/48 [58] Field 01 Search 162/274,199, 278, 279, 162/351, 352, 353, 354, 363, 366, 374, 211

[56] References Cited UNITED STATES PATENTS 2,428,921 10/1947 Scofield162/366 2,544,572 3/1951 Vickery 162/279 3,218,228 11/1965 Wagenknecht162/274 3,298,904 1/1967 LeCompte, Jr 162/274 3,393,123 7/1968 Klingleret a1. 162/274 3,393,124 7/1968 Klingler et a1. 162/352 3,420,736 1/1969Kwasniewski 162/274 3,446,702 5/1969. Buchanan 162/352 X 3,574,0564/1971 Jud et a1. 162/352 3,577,316 5/1971 Piette 162/352 mmmsrm3.886.428

sum 2 or 4 I FIG. 3

FIG. 8

Pmmmsm 1 m4 sum u [If 4 ADJUSTABLE SLOT SUCTION BOX COVER BACKGROUND OFTHE INVENTION In felt manufacturing procedures a suction pipe or box isoften utilized. The suction pipe is connected to a source of suction andhas a number of openings on its periphery to subject the material tovacuum as desired in the manufacturing process. Additionally, a vacuumpipe cover is employed over which the material can be placed andhandled. The cover is designed to permit communication between thematerial being worked on and the openings in the suction pipe to utilizesuction in the operational processes.

The conventional type of suction pipe cover is made in one or twopieces. The cover has a rigid body portion and slots positioned betweenseparated portions on the body to provide communication to the openingsin the suction pipe. The cover is rigidly mounted to the suction pipe.In some designs, the slot widths are fixed in dimension and there is nomeans for adjustment of the slot width to adjust the amount of accessthe suction openings have to the material on the surface of the cover.In other designs, the machine must be shut down in order to readjust theslotted lips in order to get a new slot width. With radical changesconstantly being made in the newer press felt designs, it is difficult,time consuming and uneconomical to make changes for proper operation. Asa result, the vacuum conditioners are not operated properly for alltypes of felt designs presently in use.

There is no question that a need is present for a means of quickly andefficiently adjusting the slot widths on a suction pipe cover toaccommodate all types of felt designs and insure proper operation of themachinery.

SUMMARY OF THE INVENTION With the above background in mind, it is amongthe primary objectives of the present invention to provide a multi-piecesuction pipe cover which permits rapid and efficient adjustment of slotwidths for particular felt designs. The cover is designed so that it caneasily be adjusted to a variety of different slot widths depending uponthe felt material to be handled. The adjusting of the slot widths can becarried out quickly and efficiently and the top wear surface of thecover can be changed rapidly and efficiently when desirable.

The present design includes the base which is fastened to the suctionpipe or box. The base has been slotted to a maximum size of a slot orslots for the intended use. Wear strips of varied widths are fitted tothe base in an interengaging manner such as by the use of dovetailedsurfaces or T-shaped surfaces. In this manner the strips can only beremoved by sliding them in respect to the fixed base. The interengagingportion are varied axially with respect to the wear strips so that byinterchanging and reversing the strips it is possible to adjust thewidth of one or more of the slots in the cover base. End stops or decklefingers are supplied at each end of each slot to assure end seals.

The cover may be designed so any number of the lands are adapted toreceive wear strips to adjust adjacent slots. By using various widths ofwear strips, further adjustments in slot width can be accomplished inaddition to the axial positioning of the interengaging surfaces on thewear strips and the lands of the cover base. Furthermore, the whole topwear surface may be formed by wear strips which can be replaced quickly,easily and much cheaper than with known previous designs.

Therefore, in summary, an adjustable slot cover is provided which isadapted to be mounted on a suction box or pipe having openings thereinin communication with the source of suction. The cover includes a basehaving means thereon for mounting the base to a suction pipe. Surfacesare on the base forming alternate lands and at least one slot with theslots in alignment with the openings in a suction pipe when the base ismounted thereon. A plurality of wear strips are provided with each stripadapted to be removably mounted on a land. Finally, interengageablesurfaces are on at least one land adjacent to a slot and each strip withthe interengageable surfaces positioned so that when a predeterminedpattern of strips are removably mounted on the lands and interengagedtherewith the position of the strips will define the exposed width ofthe slots thereby permitting adjustment of the slot sizes by thearrangement of strips on the base.

With the above objectives and summary of the invention in mind,reference is had to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is an exploded perspective view of the slot cover of theinvention and a suction pipe for mounting the slot cover thereto;

FIG. 2 is a top plan view of the slot cover of the invention and asuction pipe therefor in assembled condition with arrows showing thedirection of felt travel thereover;

FIG. 3 is a fragmentary sectional view of the slot cover of theinvention showing the configuration of the slot cover between slotopenings;

FIG. 4 is a fragmentary top plan view of the slot cover of the inventionmounted to a suction pipe;

FIG. 5 is a fragmentary sectional elevation view thereof taken along theplane of line 5-5 of FIG. 4;

FIG. 6 is a fragmentary top plan view of an alternate embodiment of theslot cover of the invention mounted to a suction pipe;

FIG. 7 is a fragmentary sectional elevation view thereof taken along theplane of line 77 of FIG. 6 with an arrow showing the direction of travelof felt across the assembly; and

FIG. 8 is a sectional side elevation view of a further alternateembodiment of the slot cover of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1-5 show one embodimentof the slot cover 20. A suction pipe 21 is depicted on which the slotcover is adapted to be mounted. The suction pipe 21 has a hollow centralchamber 22 open at one end 23 for connection to a source of suction andsealed at the opposite end 24 by means of an end cap 25 affixed thereon.Open end 23 can be affixed in any conventional manner to the source ofsuction such by a threaded interengagement with a corresponding threadedouter surface on end 23.

Two parallel rows of aligned openings 26 are on the peripheral surfaceof the pipe 21. Slots 26 provide communication between the exteriorsurface of pipe 21 and the interior chamber 22 thereof for withdrawal ofair therefrom by the source of suction through open end 23.Additionally, a pair of aligned rows of parallel bolt holes 27 are onthe outer peripheral surface of pipe 21 for assembly with the slot coverin the manner described below.

The suction pipe 21 may be constructed in a manner in which end plates28 and 29 are welded to cover the opposing ends of the pipe respectivelyand nipple 30 extends axially from end plate 28 and nipple 31 extendsaxially outwardly from end plate 29. End cap 25 then closes off nipple30 in any conventional sealing manner such as by welding. Therefore theentire suction pipe is welded air tight except for slots 26 over whichslot cover 20 is placed and, of course, the open end air outlet portion23. A pump, eductor or some other similar removal source is connected toend 23 and the only opening remaining to permit entry of air is throughslots 26 on the top of the pipe. Bolt holes 27 are naturally sealed whencover 20 is fastened to pipe 21.

The slot cover includes a base portion 32, a plurality of wear strips 33further identified as 34, 35 and 36, and a number of deckle fingers orend stops 37.

The base portion in the desired configuration can be constructed in aconvenient manner such as machinery from one piece of phenolic laminateor it may be machined or molded from polyethylene material. No portionof base 32 forms a wear surface for the felt handling during operation.The entire wear surface is provided by the wear strips 33 and the decklefingers or end stops 37.

Base 32 has a central curved undersurface 38 which conforms to the outersurface of the suction. pipe 21. The central arcuate portion 38terminates in a pair of opposed longitudinal end base portions 39 witheach end base portion containing a plurality of holes 40 along itslength. Each hole 40 is drilled oversize so a threaded screw 41 passesthrough to the threaded opening 27 in the pipe. Screws 41 threadedlyengaged with openings 27 in the suction pipe to rigidly mount base 32 tothe outer surface of pipe 21 and to prevent air from passing throughopenings 27 in pipe 21.

The upper surface of base 32 is formed of alternate lands and slots. Asshown, there are three lands 42 which define a pair of parallel slots 43therebetween. At the base of each slot 43 there are a plurality ofaligned openings 44 which communicate with openings 26 in the outersurface of suction pipe 21 to provide communication between the slots 43and the source of suction.

Defining slots 43 are three lands 45 which are upward projections ofbase 32. The lands 45 have trapezoidal shaped projections 46 extendingupwardly therefrom. Projections 46 from dovetail projections forengagement with similar dovetail recesses 47 in the undersurface of eachwear strip 33. Therefore, when a wear strip 33 is slid axially ontoprojection 46 the projection 46 will mate with the similarly shapedtrapezoidal recess 47 to fix the wear strip in position. The beveleddovetailed surfaces 46 on projection 45 and on the surfaces of wearstrip 33 forming recess 47 interengage to hold the wear strip inposition.

As shown in FIGS. l-5, projections 46 are of the same shape and size sothat any of the three wear strips 33 which have identical shape and sizerecesses 47 may be positioned on any of the lands 45. In this manner,

the wear strips can be interchanged to facilitate adjustment of the slotwidths.

Adjustment is accommodated in two manners. First, the wear strip mayhave a wider lateral dimension as, for example, wear strips 34 and 36are wider than the third wear strip 35. Therefore; when a wider wearstrip is connected to a particular projection in a dovetailedarrangement a portion of the strip will extend into the slot 43 as shownin FIGS. 4 and 5. Similarly, in FIGS. 4 and 5, it can be noted thatstrips 35 and 36 do not have the same projection into slot 43 so thatthe slot 43 between wear strips 35 and 36 is wider. By interchangingstrips 34, 35 and 36, the slots 43 can be adjusted as desired.

In addition to the difference in lateral dimension of the three wearstrips 33, and additional adjustment feature is provided by thepositioning of dovetail recess 47. In wear strip 35, the recess issubstantially centered on the undersurface of the wear strip whereas inrespect to wear strips 34 and 36 the recess is axially offcenter therebyproviding a greater portion of the wear strip on one side of theinterengagement recess than on the other. Therefore, when these wearstrips are interchanged or reversed in direction with respect to lands45, the slots 43 will be adjusted in width accordingly. It can bereadily seen how the versatility in positioning of recesses 47 and inthe actual lateral widths of the wear strips 33 can be utilized inadjusting the width of slots 43 which are exposed to the exterior of thecover. There are a variety of different arrangements of positioning forthe recesses 47 and for the widths of the wear strips 33 to provide aninfinite variety of slot size adjustments for slots 43.

Once the wear strips 33 have been positioned as desired on base 32 endstops or deckle fingers 37 are slid into position at the ends of slots43 to form end seals. Each deckle finger 37 has an upwardly standingbody portion 48 and a flange base portion 49. The flanged base portionis engaged by retaining surfaces on the lands 45 and the wear strips 33so as to be held in position and to close of the ends of each slot 43.

Deckle fingers 37 are slidable axially within slots 43 so that they canbe moved to correspond to the width of a web of felt material passingacross the top of the assembly. In this regard, particular reference ismade to FIGS. 5 and 2 of the drawings with arrows depicting thedirection of travel of the felt material 50. By adjusting fingers 37 toa position in engagement with the edge of the felt material 50 on bothsides of the material as it passes over a slot, a sealing arrangement iseffected. The deckle fingers 37 form a seal so that all of the airpassing through slots 44 in the cover and through openings 26 in thepipe must pass through the felt material. Naturally, when a differentwidth of felt material is employed, fingers 37 may be slidably adjustedaccordingly to form a similar seal. Since the felts in general use arerelatively tight in structure, air does not readily pass through andtherefore tends to restrict the air flow and build up a vacuum insidethe pipe assembly. In the above manner, the deckle fingers regulate theeffective open length of the slots and prevent air leakage from a slotopening which may be outside the edge of the felt.

Attention is directed to FIGS. 2 and 3 of the drawings whichparticularly show the configuration of the base of slots 43 in cover 20which are positioned between slots 44 through which air passes to thepipe. These intermediate lands or islands 51 are tapered to an apex, asshown, and cover the metal ribs 52 between slots 26 on pipe 21. Thetapered shape of islands 51 assist in keeping felt material frombuilding up on the flat metal ribs 52 and consequently causing streaksin the material.

An alternate embodiment is shown in FIGS. 6 and 7 of the drawings.Suction pipe 21 has slot cover mounted thereon. The mounting isaccomplished by means of angle brackets 53 one on each side of cover20'. Each angle bracket 53 is connected to vacuum pipe 21 by means ofthreaded bolts 54 which are in threaded interengagement with receptivethreaded holes 27 in pipe 21. The undersurface of the head of bolt 54engages with the bracket surface holding the bracket to the suction box21. A plurality of bolts 54 are spaced along the length of cover 20' toassure that the base 55 of the cover is held in tight engagement withsuction pipe 21. As shown, angle bracket 53 bears against base 55 andagainst suction pipe 21 to hold the base in fixed position.

Base 55 has three lands 56, 57 and 58 extending upwardly therefrom. Thelands are spaced to provide a pair of slots 59 and 60 therebetween. Thecentral land 57 forms an upper central wear surface and is of one piececonstruction with the remainder of base 55. In contrast the outer twolands 56 and 58 terminate in a pair of upward Tshaped projections 61 and62 respectively which extend the length of cover 20. Slidably mounted onthe T-shaped projections 61 and 62 are a pair of wear strips 63 and 64respectively. The undersurface of each of the wear strips 63 and 64contains a T-shaped recess which corresponds in size to T- shapedprojections 61 and 62. lnterengaging surfaces as shown on projections 61and 62 and on wear strips 63 and 64 hold the wear strips in position andpermitting only sliding movement for removal of the strips from theremainder of cover 20'. The interengagement is achieved between theouter surface of flanges 65 of projection 61 and the surroundingsurfaces 66 of strip 63 and the outer surfaces of flanges 67 ofprojection 62 and the surrounding surfaces 68 of strip 64 respectively.Once again as in the previously discussed embodiment, the outerconfiguration particularly the lateral width of each wear strip 63 and64 determines the amount of the wear strip which extends into the slotopening thereby determining the size of the slot opening to the topsurface of cover 20'. An additional feature which contributes toadjustment of slot size is the positioning of the recesses in theundersurface of wear strips 63 and 64 particularly in regard to whetheror not it is aligned with the central axis. By shifting the location ofthe recess, the mating of the T-shaped recess with the T-shapedprojections determines the position of the wear strip and in turn theamount of the wear strip which extends over slots 59 and 60 to cover aportion thereof. In this manner, by providing a number of differentsized wear strips and a number of different wear strips with off-setrecesses in their undersurfaces, a great variety of slot widthvariations can be accomplished.

It should be kept in mind that although a one-piece base and projectionembodiment is shown in FIGS. 6 and 7, the T-shaped projection could bein the form of a metal T-bar bolted to the remainder of the base 55.Additionally, the embodiment of FIGS. 6 and 7 shows a central landportion without a removable wear strip for adjustment and the embodimentof FIGS. 1 to 5 shows all three land structures with removable andadjustable wear strips. Furthermore, it can be readily envisioned howthe projections can be located on the wear strips and the recesses inthe land surfaces for interengagement in a similar manner as describedabove. A great number of different combinations of one-piece landstructures along with replacement wear strip structures can be combinedas desired.

Additionally, although there are three land portions on base 55 and twointermediate slots in both of the embodiments shown, it can readily beenvisioned how it is possible to construct the cover with any number ofland portions with appropriate slots located in between each adjacentpair of land portions of a cover, for example, one slot between two landportions.

It can also be readily envisioned that cover 20 can be designed to fit avariety of different configurations for the suction base member. Thiswould naturally include suction boxes as well as suction pipes. Forexample, FIG. 8 depicts a further alternate embodiment for a coverwherein cover 69 has a trapezoidal shaped undersurface 70 to accommodatea corresponding trapezoidal shaped suction box member. In all otherrespects, the cover would operate as in the previously discussedembodiments. The configuration of the undersurface of cover 69 isdesigned merely to accommodate its connection to the appropriate suctionsource member.

In summary, the removable wear strips provide a means for immediateadjustment of slot width at all times to control the vacuum on a widerange of felt designs. Additionally, individual replacement of wearstrips is possible rather than the necessity of replacing an entirecover when it is desirable or necessary.

Thus the above discussed objectives of the invention, among others, areeffectively attained.

I claim:

1. In combination:

a suction pipe, surfaces of said suction pipe defining at least onelongitudinal opening into the suction pipe interior;

an adjustable slot cover for said suction pipe, said cover including abase, means on said base for mounting the base to said suction pipe infixed position, surfaces of the base forming alternate longitudinallands and defining at least one longitudinal slot between said lands,said slot being in alignment with said suction pipe opening; and,plurality of interchangeable wear strips, each of said wear stripsslidably engaging a land of said base; said wear strips each comprisingan upper wear surface of predetermined width and an undersurface portionincluding means thereon for removably interlocking and interengagingwith a land, said interlocking means being located off center withrespect to said wear surface so that the spacing between the wear stripsengaging alternate lands can be altered to vary the exposed width ofsaid slot.

2. The invention in accordance with claim 1 wherein each of said wearstrip undersurface portions includes a longitudinally extendingtrapezoidal recess and each of said lands has a complementarytrapezoidal shape in section.

3. The invention in accordance with claim 1 wherein each of said wearstrip undersurface portions includes at least one L-shaped clamp hassurfaces bearing against the base of the cover and surfaces bearingagainst the suction box and a passageway therethrough to receive a bolt,the bolt threadedly interen gaged with an opening in the suction pipe torigidly hold the clamp to the cover and the suction pipe and retain thecover in fixed position with respect to the suction pipe.

7. The invention in accordance with claim 1 wherein the base is formedof polyethylene material.

8. The invention in accordance with claim 1 wherein the base is formedof a phenolic resin material.

1. In combination: a suction pipe, surfaces of said suction pipe defining at least one longitudinal opening into the suction pipe interior; an adjustable slot cover for said suction pipe, said cover including a base, means on said base for mounting the base to said suction pipe in fixed position, surfaces of the base forming alternate longitudinal lands and defining at least one longitudinal slot between said lands, said slot being in alignment with said suction pipe opening; and, a plurality of interchangeable wear strips, each of said wear strips slidably engaging a land of said base; said wear strips each comprising an upper wear surface of predetermined width and an undersurface portion including means thereon for removably interlocking and interengaging with a land, said interlocking means being located off center with respect to said wear surface so that the spacing between the wear strips engaging alternate lands can be altered to vary the exposed width of said slot.
 2. The invention in accordance with claim 1 wherein each of said wear strip undersurface portions includes a longitudinally extending trapezoidal recess and each of said lands has a complementary trapezoidal shape in section.
 3. The invention in accordance with claim 1 wherein each of said wear strip undersurface portions includes a longitudinally extending ''''T''''-shaped recess and each of said lands has a complementary ''''T''''-shape in section.
 4. The invention in accordance with claim 1 wherein there are three lands on the base, three wear strips interchangeably mounted on the three lands, and the three lands with the three wear strips mounted defining two longitudinal slots therebetween.
 5. The invention in accordance with claim 1 wherein there are deckle fingers removably mounted on the base and positioned at each end of the slot to form end air seals.
 6. The invention in accordance with claim 1 wherein at least one L-shaped clamp has surfaces bearing against the base of the cover and surfaces bearing against the suction box and a passageway therethrough to receive a bolt, the bolt threadedly interengaged with an opening in the suction pipe to rigidly hold the clamp to the cover and the suction pipe and retain the cover in fixed position with respect to the suction pipe.
 7. The invention in accordance with claim 1 wherein the base is formed of polyethylene material.
 8. The invention in accordance with claim 1 wherein the base is formed of a phenolic resin material. 